Semiconductor processing (e.g., fabrication) can be used to form semiconductor devices, such as integrated circuits, memory devices, microelectromechanical devices (MEMS), etc.
Examples of memory devices that can be formed by semiconductor processing include, but are not limited to, volatile memory (e.g., that can require power to maintain its data), such as random-access memory (RAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), among others, and non-volatile memory (e.g., that can provide persistent data by retaining stored data when not powered), such as NAND flash memory, NOR flash memory, read only memory (ROM), electrically erasable programmable ROM (EEPROM), erasable programmable ROM (EPROM, among others.
Semiconductor processing can involve forming features (e.g., patterns) on and/or in a substrate, such as a semiconductor substrate (e.g., of silicon), that may be referred to as a wafer. In some examples, one or more materials, such as silicon-based materials (e.g., silicon oxide (SiO), silicon nitride (SiN), tetraethyl orthosilicate (TEOS), and/or polysilicon), conductors, etc. may be formed on the semiconductor. For instance, a deposition process, such as physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), electrochemical deposition and/or molecular beam epitaxy, among others may be used to form the materials on the semiconductor.
Subsequently, portions of the one or more materials, and in some instances, portions of the semiconductor, may be removed, such as by wet and/or dry etching, to form the features. In some examples, the features may have high aspect ratios (e.g., ratios of height to width or diameter) and may be referred to as high-aspect-ratio (HAR) features. For example, the features might be separated from each other by HAR openings.
During processing, the substrate and the features may be subjected to wet processing, such as wet cleaning, and subsequent drying. For example, wet cleaning can be helpful to remove residue left behind, such as by the removal process or other processing.